Abstract:

BACKGROUND: Previous studies have shown that double layer cells implantation improves retention rate of vascular prosthesis endothelial cells. The fibrinolysis ability of endothelial cells (ECs) is improved after transfection with tissue plasminogen activator (tPA).
OBJECTIVE: In order to enhance the antithrombotic ability and adhesion to polytetrafluoroethylene (PTFE) of ECs, tPA gene was introduced into ECs by pseudotyped retroviral vector. And endothelial nitric oxide synthase (eNOS) gene was introduced into smooth muscle cells (SMCs) to research whether eNOS gene transfection can inhibit the proliferation of neointimal hyperplasia with grafted both SMCs and ECs transfected with tPA.
METHODS: The SMCs and ECs were implanted in PTFE grafts successively according to the following combination: ECs+SMCs, ECs/tPA+SMCs, ECs+SMCs/eNOS, ECs/tPA+SMCs/eNOS. Twenty-four adult New Zealand rabbits were randomly divided into 4 groups (n = 6). The above four types of PTFE covered with ECs and MSCs were transplanted respectively into the abdominal aorta of rabbits in four groups as bypass graft.
RESULTS AND CONCLUSION: There was no difference in neointimal thickness between grafts seeded with ECs+SMCs and grafts seeded with ECs+SMCs/eNOS (P > 0.05). But compared with the grafts seeded with ECs/tPA+SMCs/eNOS, the neointimal thickness on grafts seeded with ECs/tPA+SMCs was significantly thicker (P < 0.05), while the neointimal thickness on grafts seeded with ECs+SMCs/eNOS was significantly thinner (P < 0.05). tPA gene in ECs can promote neointimal hyperplasia in the vessel graft seeded with ECs+SMCs, but eNOS gene in SMCs can inhibit this effect.